2015-06-21: In which I Re-learn the Value of Testing Equipment Well in Advance of Actually Needing it

Posted on June 22, 2015


One month until South Africa. Got my tickets, permits, licenses, ammo, rifle, pelican case, binos, sling, sticks, and most of the other sundries for the trip.

One of the last steps, zeroing my new scope and getting dope for both my main load (Remington Managed Recoil) and my Eland Load (Safari Arms 175 gr Swift A-Frame).

Having grown up in the era of Oehler ballistic chronographs, I saw my first Magnetospeed V3 at the Steel Safari, which we used to get a better velocity on my AI AT. I said immediately, “I need that.”

Interestingly, the un-boresighted scope needed only ~1 mil of elevation and no wind to be on steel at 100 yards. Unfortunately, I ran into a major problem: the combination of low scope mount and large windage knob meant empty cases would bounce off the scope back into the action of the Tikka. I briefly thought about moving the scope forward or backwards but the eye relief was perfect. So, upon speaking with my friend, an ex-employee of Nightforce, I decided that the second-best solution is to put a picatinny rail and raise it up 0.25″… I knew I put an adjustable cheek piece on this rifle for a reason.

After abandoning plans to zero, I unboxed the Magnetospeed.  It was actually a bit trickier to install than I thought. To get the sensor deck at the right height, but not so high as to turn it into plastic shrapnel on firing, I had to use every spacer provided, plus the thin rubber pad. Using the Magnetospeed was a snap, and the fact that it stores the ballistics data on a MicroSD card in CSV format is very trick. One tip: don’t be afraid to crank down the thumbscrew on the strap. Also, shooting a hard kicking gun, check the sensor position after every shot.  I got lucky… after the third shot, the muzzle had slipped inside the outer edge of the rubber pad, that would have been very embarrassing if I’d shot the sensor off…

About to start gathering data:

Well worth the money

Well worth the money

140 gr Remington Core-Lokt @ 2750 ftps

140 gr Remington Core-Lokt @ 2750 ftps


For the records:

Cartridge 7mm Rem Mag
Maker Remington Managed Recoil
Bullet Core-Lokt
Weight 140gr
BC 0.388

Min 2731 Max 2778
Avg 2750 S-D 17.1
ES 47

Shot Speed
1 2778 ft/s
2 2731 ft/s
3 2742 ft/s
4 2750 ft/s
5 2763 ft/s
6 2740 ft/s

Cartridge 7mm Rem Mag
Maker Safari Arms
Bullet Swift A-Frame
Weight 175gr
BC 0.493

Min 2699 Max 2732
Avg 2712 S-D 12.2
ES 33

Shot Speed
1 2732 ft/s
2 2706 ft/s
3 2718 ft/s
4 2702 ft/s
5 2699 ft/s
6 2716 ft/s


Posted in: Hunting